pingd constraint is not adhered to sporadically (OPENAIS HEARTBEAT)

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Environment

SUSE Linux Enterprise Server 11
SUSE Linux Enterprise Server 11 Service Pack 1

Situation

After setting up a cluster with a pingd Resource according to documentation a constraint that needs this pingd is not adhered to.

The configuration of the pingd Resource might look like this

primitive pingd ocf:pacemaker:ping \
        operations $id="pingd-operations" \
        op monitor interval="10" timeout="60" \
        params host_list="192.168.67.2" name="pingd" dampen="20s" multiplier="100"

Most commonly a placement strategy like

location precious_on_connected_node precious \
        rule $id="precious_on_connected_node-rule" -inf: not_defined pingd or pingd lte 0

which would place resource "precious" on a node that has contact to the ping target. The effect seen is, the ping target can be reached but the constraint seemingly has no effect.

Resolution

The problem comes from the dampen parameter being bigger than the monitor interval.
This will be fixed in the future.
As a solution and workaround all that has to be done is to make the dampen smaller than the monitor or the monitor bigger than the dampen. For example

primitive pingd ocf:pacemaker:ping \
        operations $id="pingd-operations" \
        op monitor interval="10" timeout="60" \
        params host_list="192.168.67.2" name="pingd" dampen="5s" multiplier="100"

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